1. Field of the Invention
The present invention relates to a rotor provided with a squirrel-cage conductive body and used for, for example, an induction motor, and to a manufacturing method thereof.
2. Description of the Related Art
Recently, there is an increased need for a rotational electric motor operable at a high speed. When an electric motor operates at a high speed, centrifugal force acting on components of the rotor increases, which results in deformation of a conductive end ring, or possibly, in breakage thereof. In order to prevent it, a reinforcing member, for example, is attached to the conductive end ring (refer to JP 3-261354 A, JP 10-127022 A, JP 2838896 B, and JP 2911315 B). However, such a reinforcing member needs to be specially designed, depending on the shape of the rotor, particularly on the shape of the conductive end ring. Accordingly, the number of components that have to be managed is increased, resulting in increased cost. If the rotor has a complicated shape, the cost for producing the reinforcing member is thereby increased. Further, when an iron core of the rotor is intended to be skewed, the amount of skew may be restricted due to limitation related to the size and the shape of the reinforcing member.
Reference should also be made to Kazuhiko Sakaki, “Overview of cold spray technology and cold sprayed light metals coatings,” Journal of Japan Institute of Light Metals, Vol. 56, No. 7 (2006), pages 376 to 385, in which the principle of a cold spray process, a process for forming aluminum/titanium coatings and properties of such coatings are described.
According to the present invention, a rotor, particularly a rotor that can be reinforced regardless of a shape of a conductive end ring, and a manufacturing method thereof are provided.